Improvement in screw-drivers



w. F. PATTERSON.

.s-crew-D-rivlerh THE GRAPHIC CO.PRUTO.-LITH.39& .4I PARK PLAGLN-Y.

No. 161,056 .Paten ted March23',1875.

UNITED STATES PATENT O FIo,

WILLIAM F. PATTERSON, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN SCREW-DRIVERS.-

Specification forming part of Letters Patent No. 161,056, dated March 23, 1875; application filed February 20, 1875.

To all whom it may concern:

Be it known that 1, WILLIAM F. PATTER- soN, of Boston, in the county of Suffolk, State of Massachusetts, have invented a certain new and useful Improvement in Screw-Drivers, of which the following is a description sufficiently full, clear, and exact to enable any person skilled in the art or science to which my in vention appertains to make and use the same, reference being had to the accompanying drawing, forming a part of this specification, in which- Figure 1 is an isometrical perspective view.

My invention is designed as an improvement upon those patented to me February 24:, 1874, numbered 147,785, November 24., 1874, numbered 157,102, and January 19, 1875, numbered 158,807 and consists in a novelconstruction and arrangement of the parts, as hereinafter more fully set forth and claimed, by which the simplicity and effectiveness of this class of screw-drivers are greatly enhanced.

In the drawing, A represents the main blade of the driver, which is provided with the elongated slot B and hole J. Attached to the main blade by the set-screw I) there is a detachable or auxiliary blade, L, having a point at each end, and provided with a slot, B, corresponding with the slot B, for renderin g it adjustable longitudinally thereon. Sliding on the blade A there is an adjustable clamp, E, provided with a looking or fastening device consisting in part of the bar H, from one end of which a stud, I, projects inwardly' through a hole in the side of the clamp, the other end being provided with the long pin F working in holes in two flanges projecting from the edge of the same, as shown. Around the pin F there is a coiled spring, G, one end of which presses against the flange nearest the bar H, and the other against a cross-pin (not shown) in the pin F. Project ing upwardly from the clamp E there is a lip or flange, K, forming a step or socket, in which the lower end of the blade L rests when in working position. This flange is made thinnest at its upper end, to render the socket thus formed flaring or tapering, so that as the auxiliary blade is crowded into it it will wedge and be held firmly in position.

To adjust.the driver for use, the clamp E is slipped along the body of the blade A until the stud I is forced into the hole J by the expansive action of the spring G. The blade L is then turned to bring forward the point which it is desired to use, the opposite point 7 being forced downwardly into the socket between the flange K and bladeA firmly secured together by the set-screw D.

I do not herein claim anything shown or described in either of said Letters Patent when in and of itself considered; but 7 Having thus explained my invention, what I claim, is-

The improved screw-driver described, the same consisting of the blade A, reversible blade L, screw D, and spring-clamp E, provided with the tapering flange K, all constructed and arranged to operate substantially as and for the purpose specified.

WILLIAM F. PATTERSON.

Witnesses:

O. A. SHAW, H. E. METOALF. 

